Desktop Viewer installer makes readability assumptions concerning the end user’s appearance settings.
The worst (so far) is assuming a black or dark text color setting, for text superimposed over a graphic.
I use a reverse tone, high contrast scheme with off white text, on charcoal background. This is what the installer dialogs look like:
Basically any text that is going to be superimposed over a graphic should be hardset to a dark color, so as to be always visible.
Unfortunately that is the rare configuration problem: Windows doesn’t promote theming much (although it is definitely possible), which causes the majority of users sticking with the default theme, and the majority of developers not being sensibilized. (similar problems: hidpi support before it became mainstream, etc.)
When applications use system colors, background and text color must be a match pair (e.g. MenuColor + MenuText). Then it remains in the responsibility of the theme creator.
When hardcoding one of them (e.g. here white image, but also often black text) the other one must also be hardcoded (here text).